Voice control of apparatus is becoming more common and there are now well developed technologies for speech recognition particularly in contexts that only require small vocabularies.
However, a problem exists where there are multiple voice-controlled apparatus in close proximity since their vocabularies are likely to overlap giving rise to the possibility of several different pieces of apparatus responding to the same voice command.
It is known from U.S. Pat. No. 5,991,726 to provide a proximity sensor on a piece of voice-controlled industrial machinery or equipment. Activation of the machinery or equipment by voice can only be effected if a person is standing nearby. However, pieces of industrial machinery or equipment of the type being considered are generally not closely packed so that whilst the proximity sensor has the effect of making voice control specific to the item concerned in that context, the same would not be true for voice controlled kitchen appliances as in the latter case the detection zones of the proximity sensors are likely to overlap.
One way of overcoming the problem of voice control activating multiple pieces of apparatus, is to require each voice command to be immediately preceded by speaking the name of the specific apparatus it is wished to control so that only that apparatus takes notice of the following command. This approach is not, however, user friendly and users frequently forget to follow such a command protocol, particularly when in a hurry.
It is an object of the present invention to provide a more user-friendly way of minimising the risk of unwanted activation of multiple voice-controlled apparatus by the same verbal command.